But there are compelling stories behind those two stars. On Sunday, five men with PRs of 2:14 will try to make the jump to the next tier of American marathoning, the 2:11-2:12 range that puts you among the ten best in the country. Perhaps the most likely candidate is Sean Quigley, until now a journeyman runner, but someone whose lifetime of mostly solo training should serve him well in Chicago’s late miles.

Quigley graduated from La Salle University in Philadelphia in 2008 with promising PRs of 13:30 for 5000 meters and 28:03 for 10,000 meters and two top-six finishes at the NCAA 10K championship. Instead of taking the usual route of moving and joining a training group, Quigley stayed in Philly so that he could keep working with his college coach, Charles Torpey, a sassy, beloved figure in East Coast running for decades.

After the usual post-graduation growing pains, Quigley began to hit his stride on the roads in the second half of 2010. He won the national 20K title in September of that year, and was the first American at the 2010 world half marathon championship. As he had in college, he did almost all of his weekly 130 miles by himself.

On July 1, 2011, Quigley did an 8-mile tempo run, with Torpey accompanying him on a bike. After the tempo run, “I left him where I finished to do my cooldown,” Quigley remembers. “He was going back to his car to put his bike away. When I got back I was like, ‘Where is he?’ Then I saw ambulance lights in the distance. I thought, ‘Oh, he must have stopped to see what happened.’ I didn’t see him in the crowd of people there, and then I knew.” Torpey, 58, had collapsed and died from a heart attack.

“I knew the best way to honor Torp was to keep training,” Quigley says. He and Torpey had been working toward the January 2012 Olympic Marathon Trials as the site of Quigley’s debut at the distance. Quigley looked into moving to Boulder or joining the Mammoth Track Club in California. He opted for Boulder, where he’s lived since, coached by two-time Australian Olympic marathoner Lee Troop.

Things went acceptably for Quigley in Houston at the Trials, a 2:14:12 debut, good for 16th place in arguably the deepest American field in history.

And then….not much, either for Quigley or many of the other men who set PRs that day. Quigley agrees that little momentum seems to have built since the Trials, where Ryan Vail’s 2:12:43 was good for only 11th place. This year, only Jason Hartmann’s 2:12:12 at Boston is faster, and the top rank of U.S. marathoning has remained what Quigley calls “the big four”: Ritzenhein, Ryan Hall, Meb Keflezighi, and Abdi Abdirahman, all over the age of 30.

Quigley hopes to take a big step closer to that rank on Sunday. “I’m trying to run 2:11, 2:12,” he says. “I believe I can handle that pace and not blow up.” Quigley says the flooding that hit Boulder in September didn’t interfere with his training for Chicago.

As he did at La Salle, as he did post-collegiately under Torpey, and as he mostly does in Boulder, Quigley accepts that he could be running a lot by himself on Sunday. “I’ve tried to get a feel for what other [Americans with similar PRs] are thinking, but some of them are being cryptic,” Quigley says. “They just say, ‘Run a PR.’

“I’m going to try my best to get to halfway in 65:30 to 66:00,” Quigley says. “If there’s someone with me, great.”